The present invention relates to a circuit board for a semiconductor device and a method of making the same.
In FIG. 15, a conventional circuit board 10 for a semiconductor device is shown. A metal plate 14 for radiating heat is adhered on a bottom face of a base board 12 of the circuit board 10 by an adhesive.
The base board 12 has a chip hole 15, in which an IC chip 17 is accommodated, and a set of wire patterns 18, which is electrically connected with the IC chip 17, is printed on an upper face of the base board 12. An upper face of the metal plate 14 corresponding to the chip hole 15 acts as a chip mounting section 16.
The conventional circuit board 10, which is formed into a small piece, is made by the steps of: forming the base board 12 having the chip hole 15 and the set of wire patterns 18; and fixing the metal plate 14 on the bottom face of the base board 12. Each circuit board 10 is made by these steps, so the manufacturing efficiency cannot be increased.
To improve on the method of making the conventional circuit board 10, the inventor proposed another method as shown in FIG. 16. In the method shown in FIG. 16, a plurality of circuit boards are made by the steps of: forming a common base board 12 having a plurality of chip holes 15 and a plurality of sets of wire patterns 18; fixing a common metal plate 14 for radiating heat on a bottom face of the base board 12 by an adhesive; and cutting the base board 12 and the metal plate 14 along borders between adjacent pattern units "A" by cutting means, e.g., a rooter, a die set, a press machine. By this method, a plurality of circuit boards 10, each of which is formed into a small piece, can be made.
In the method shown in FIG. 16, the common metal plate 14 is fixed by the adhesive in one step, so the manufacturing efficiency of the circuit boards 10 can be improved.
However, as shown in FIG. 17, flashes 19 are apt to be formed in cut faces of the metal plate 14.